Research On Modeling Functionality Of Digital Circuit And Control Path Verification Method

With the rapid development of integrated circuit technology,the design scale of integrated circuit is increasing.The complexity of functionality increases exponentially with the design scale.The functional verification spends 50%~80% of the design cycle.Therefore,the functional verification has become a bottleneck in design.This paper research on the functional verification of integrated circuit.We use a specification-based semi-formal verification method,which combines simulation with formal verification.This method adopts formal model to describe the functional points,then traverses the formal model to generate test vectors,so it overcomes the defects of simulation and formal verification.The research contents and innovations of this paper are listed as follows:1.We propose an entity-based functional point model.This functional model can describe the functional behaviors and inner entities from specification,which focuses on the functional behavior and hides the design implementation,to ensure the completeness of the functional model.2.Based on the proposed functional point model,we explore the functional verification method of control path.To generate high-quality test vectors and increase test-space coverage,this method traverses all the legal values of control-path ports in the control-sensitive stage transition,and uses the full coverage for specific boundary conditions plus a certain amount of random coverage in the data-sensitive stage transition.3.Based on the proposed functional point model,we develop an automatic verification tool.The automatic verification tool can realize efficient modeling of functional point model and automatic generation of test vectors,so it can support the efficient verification.In order to verify the validity of the proposed functional point model,this paper verifies the control path-sensitive design DMA.The experiment results show that compared with the traditional manual verification method,our functional point model-based semi-formal verification method and the automatic verification tool can greatly shorten the verification cycle and improve the efficiency of verification.